<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>图片展示显示详细说明和隐藏</title>
<meta charset='utf-8'/>
<style type="text/css">
body, ul, li, ol {
	list-style: none;
	padding: 0px;
	margin: 0px;
	font-size: 12px;
	font-family: 微软雅黑;
}
img {
	border: 0px;
}
.picList {
	width: 100%;
	float: left;
}
/*元素宽高,浮动,溢出部分隐藏*/
.picList .col {
	float: left;
	width: 300px;
	height: 200px;
	overflow: hidden;
	position: relative;
	margin: 10px 0 0 10px;
}
/*图像文字默认绝对定位*/
.picList .col img, .col a {
	position: absolute;
	top: 0px;
	left: 0px;
}
/*图像和元素内部同宽,高度一般是170px*/
.picList .col img {
	width: 100%;
}
/*超级链接元素块级展示,默认top:160px,盖住图像底端10px,背景半透明
  高度= 180px + 2*padding10px = 200px
 */
.picList .col a {
	display: block;
	width: 280px;
	height: 180px;
	top: 160px;
	background:#000;
	color: white;
	font-style: normal;
	line-height: 25px;
	padding: 10px;
	opacity: 0.8;
	text-decoration: none;
}
</style>
</head>
<body>
<div class='picList' id="picList">
    <div class='col' id="pic1" > 
       <img src="1.jpg" />
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       </a> 
    </div>
    <div class='col' id="pic2"> 
       <img src="2.jpg" />
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    </div>
    <div class='col' id="pic3"> 
       <img src="3.jpg" />
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    </div>
</div>
<script>
  function imgDisplay(){
    var Div = document.getElementById('picList').getElementsByTagName('div');
    var divHeight = 160;
    //鼠标悬浮到元素上的时候,改变绝对定位的a元素的距离顶部的尺寸即可
    for(var i =0 ;i<Div.length;i++){
      Div[i].onmouseover = showMsg;
      Div[i].onmouseout = hideMsg;
      }
    function showMsg(){
      this.getElementsByTagName('a')[0].style.top = 0;
      }
    function hideMsg(){
      this.getElementsByTagName('a')[0].style.top = divHeight+'px';
      }
	}
	imgDisplay();
</script>
</body>
</html>

